Device for supporting a hand-held tool

Abstract

The present invention relates to a device for supporting a heavier hand-held tool, particularly a spot welding gun, comprising a tool stand provided with a support arm arrangement mounted thereon, and a constant force spring having a first end and a second end, said first end of the constant force spring being attached to said support arm arrangement, and said hand-held tool being hung from said second end of the constant force spring, wherein the constant force of the spring is such that a user of the hand-held tool is relieved from at least a substantial portion of the weight of the tool, and the drawn-out length of the spring is long enough to enable the tool to be hung in a plurality of different operation heights. Preferably, the constant force of the spring is such that the tool is hung in a weight-balanced state. A line element may be connected between the constant force spring and the tool.

What is claimed is:  
     
       1. A device for supporting a heavier hand-held tool comprising a tool stand provided with a support arm arrangement mounted thereon, and a constant force spring having a first end and a second end, 
       said first end of the constant force spring being attached to said support arm arrangement, and  
       said hand-held tool being hung from said second end of the constant force spring, wherein  
       the constant force of the spring is such that a user of the hand-held tool is relieved from at least a substantial portion of the weight of the tool, and  
       the drawn-out length of the spring is long enough to enable the tool to be hung in a plurality of different operation heights.  
     
     
       2. The device as claimed in  claim 1 , wherein the constant force of the spring is such that the tool is hung substantially in a totally weight-balanced state. 
     
     
       3. The device as claimed in  claim 1 , wherein said constant force spring is comprised of a metallic band rolled around its first end, which is an inner ring-shaped end having an axis of symmetry and said second end of the constant force spring is an outer loose end of said band, wherein said ring-shaped end is attached to said support arm arrangement such that said ring-shaped end is freely rotatable around said axis of symmetry. 
     
     
       4. The device as claimed in  claim 3 , wherein said ring-shaped end of the constant force spring is attached to said support arm arrangement journalled in a bearing. 
     
     
       5. The device as claimed in  claim 4 , wherein said first end of the constant force spring is attached to an uppermost end of said support arm arrangement. 
     
     
       6. The device as claimed in  claim 3 , wherein said ring-shaped end of the constant force spring is attached to a shaft of said support arm arrangement such as to provide sufficient clearance between the shaft and the inner diameter of the ring-shaped end, to allow the free rotation around the axis of symmetry. 
     
     
       7. The device as claimed in  claim 1 , wherein said constant force spring is comprised of a metallic band rolled around its first end, which is an inner ring-shaped end having an axis of symmetry and said second end of the constant force spring is an outer end of said band, wherein said ring-shaped end is attached to said support arm arrangement such that said ring-shaped end is freely rotatable around said axis of symmetry as the band is drawn out, and wherein the tensile force of the spring is substantially independent of the deflection of the spring. 
     
     
       8. The device as claimed in  claim 7 , wherein said ring-shaped end of the constant force spring is attached to said support arm arrangement journalled in a bearing. 
     
     
       9. The device as claimed in  claim 7 , wherein said ring-shaped end of the constant force spring is attached to a shaft of said support arm arrangement such as to provide sufficient clearance between the shaft and the inner diameter of the ring-shaped end, to allow the free rotation around the axis of symmetry. 
     
     
       10. A device for supporting a heavier hand-held tool, particularly a machine-driven tool, optionally with cables attached to it, comprising a tool stand provided with a support arm arrangement mounted thereon, a constant force spring having a first end and a second end, and a line element having a first end and a second end, 
       said first end of the constant force spring being attached to said support arm arrangement, and  
       said second end of the constant force spring being attached to said first end of the line element,  
       said hand-held tool being arranged to be suspended from said second end of the line element, wherein  
       the constant force of the spring is such that a user of the hand-held tool, during use, is relieved from at least a substantial portion of the weight of the tool, and optionally of the cables attached to it, and  
       the drawn-out length of the spring is long enough to enable the tool to be suspended in a plurality of different operation heights.  
     
     
       11. The device as claimed in  claim 10 , wherein the constant force of the spring is such that the tool is suspended effectively in a weight-balanced state. 
     
     
       12. The device as claimed in  claim 10 , wherein said support arm arrangement comprises a substantially horizontally arranged upper arm having (1) a first end to which said first end of the constant force spring is attached, and (2) a second end from which said second end of said line element is hanging, and wherein said substantially horizontally arranged upper arm is arranged for guiding the drawn-out length of the spring and the first end of said line element. 
     
     
       13. The device as claimed in  claim 12 , wherein said support arm arrangement comprises a housing provided with a substantially horizontal through bore for receiving said substantially horizontally arranged upper arm, and wherein said substantially horizontally arranged upper arm is movable along the axis of the bore. 
     
     
       14. The device as claimed in  claim 13 , wherein said support arm arrangement comprises a vertically extended support arm at which said housing is mounted such that said housing is rotatable around a substantially vertical axis. 
     
     
       15. The device as claimed in  claim 14 , wherein said vertically extended support arm is extending in a direction, which is inclined by 15-40° from the vertical direction. 
     
     
       16. The device as claimed in  claim 10 , wherein said tool stand is mounted on a trolley. 
     
     
       17. A device for supporting cables attached to a heavier hand-held tool, particularly a machine-driven tool, such as a spot welding gun intended to be used for e.g. plate works, comprising a tool stand provided with a support arm arrangement mounted thereon, a constant force spring having a first end and a second end, and a line element having a first end and a second end, 
       said first end of the constant force spring being attached to said support arm arrangement, and  
       said second end of the constant force spring being attached to said first end of the line element,  
       said cables attached to the hand-held tool being arranged to be suspended from said second end of the line element, wherein  
       the constant force of the spring is such that a user of the hand-held tool, during use, is relieved from at least a substantial portion of the weight of the cables attached to it, and  
       the drawn-out length of the spring is long enough to enable the cables to be suspended in a plurality of different operation heights.